/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <rte_lcore.h>

#include "cpu_core_map.h"

struct cpu_core_map {
    uint32_t n_max_sockets;
    uint32_t n_max_cores_per_socket;
    uint32_t n_max_ht_per_core;
    uint32_t n_sockets;
    uint32_t n_cores_per_socket;
    uint32_t n_ht_per_core;
    int map[0];
};

static inline uint32_t
cpu_core_map_pos(struct cpu_core_map *map,
                 uint32_t socket_id,
                 uint32_t core_id,
                 uint32_t ht_id)
{
    return (socket_id * map->n_max_cores_per_socket + core_id) *
           map->n_max_ht_per_core + ht_id;
}

static int
cpu_core_map_compute_eal(struct cpu_core_map *map);

static int
cpu_core_map_compute_linux(struct cpu_core_map *map);

static int
cpu_core_map_compute_and_check(struct cpu_core_map *map);

struct cpu_core_map *
cpu_core_map_init(uint32_t n_max_sockets,
                  uint32_t n_max_cores_per_socket,
                  uint32_t n_max_ht_per_core,
                  uint32_t eal_initialized)
{
    uint32_t map_size, map_mem_size, i;
    struct cpu_core_map *map;
    int status;

    /* Check input arguments */
    if ((n_max_sockets == 0) ||
        (n_max_cores_per_socket == 0) ||
        (n_max_ht_per_core == 0))
        return NULL;

    /* Memory allocation */
    map_size = n_max_sockets * n_max_cores_per_socket * n_max_ht_per_core;
    map_mem_size = sizeof(struct cpu_core_map) + map_size * sizeof(int);
    map = (struct cpu_core_map *) malloc(map_mem_size);
    if (map == NULL)
        return NULL;

    /* Initialization */
    map->n_max_sockets = n_max_sockets;
    map->n_max_cores_per_socket = n_max_cores_per_socket;
    map->n_max_ht_per_core = n_max_ht_per_core;
    map->n_sockets = 0;
    map->n_cores_per_socket = 0;
    map->n_ht_per_core = 0;

    for (i = 0; i < map_size; i++)
        map->map[i] = -1;

    status = (eal_initialized) ?
             cpu_core_map_compute_eal(map) :
             cpu_core_map_compute_linux(map);

    if (status) {
        free(map);
        return NULL;
    }

    status = cpu_core_map_compute_and_check(map);
    if (status) {
        free(map);
        return NULL;
    }

    return map;
}

int
cpu_core_map_compute_eal(struct cpu_core_map *map)
{
    uint32_t socket_id, core_id, ht_id;

    /* Compute map */
    for (socket_id = 0; socket_id < map->n_max_sockets; socket_id++) {
        uint32_t n_detected, core_id_contig;
        int lcore_id;

        n_detected = 0;
        for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
            struct lcore_config *p = &lcore_config[lcore_id];

            if ((p->detected) && (p->socket_id == socket_id))
                n_detected++;
        }

        core_id_contig = 0;

        for (core_id = 0; n_detected ; core_id++) {
            ht_id = 0;

            for (lcore_id = 0;
                 lcore_id < RTE_MAX_LCORE;
                 lcore_id++) {
                struct lcore_config *p =
                        &lcore_config[lcore_id];

                if ((p->detected) &&
                    (p->socket_id == socket_id) &&
                    (p->core_id == core_id)) {
                    uint32_t pos = cpu_core_map_pos(map,
                                                    socket_id,
                                                    core_id_contig,
                                                    ht_id);

                    map->map[pos] = lcore_id;
                    ht_id++;
                    n_detected--;
                }
            }

            if (ht_id) {
                core_id_contig++;
                if (core_id_contig ==
                    map->n_max_cores_per_socket)
                    return -1;
            }
        }
    }

    return 0;
}

int
cpu_core_map_compute_and_check(struct cpu_core_map *map)
{
    uint32_t socket_id, core_id, ht_id;

    /* Compute n_ht_per_core, n_cores_per_socket, n_sockets */
    for (ht_id = 0; ht_id < map->n_max_ht_per_core; ht_id++) {
        if (map->map[ht_id] == -1)
            break;

        map->n_ht_per_core++;
    }

    if (map->n_ht_per_core == 0)
        return -1;

    for (core_id = 0; core_id < map->n_max_cores_per_socket; core_id++) {
        uint32_t pos = core_id * map->n_max_ht_per_core;

        if (map->map[pos] == -1)
            break;

        map->n_cores_per_socket++;
    }

    if (map->n_cores_per_socket == 0)
        return -1;

    for (socket_id = 0; socket_id < map->n_max_sockets; socket_id++) {
        uint32_t pos = socket_id * map->n_max_cores_per_socket *
                       map->n_max_ht_per_core;

        if (map->map[pos] == -1)
            break;

        map->n_sockets++;
    }

    if (map->n_sockets == 0)
        return -1;

    /* Check that each socket has exactly the same number of cores
    and that each core has exactly the same number of hyper-threads */
    for (socket_id = 0; socket_id < map->n_sockets; socket_id++) {
        for (core_id = 0; core_id < map->n_cores_per_socket; core_id++)
            for (ht_id = 0;
                 ht_id < map->n_max_ht_per_core;
                 ht_id++) {
                uint32_t pos = (socket_id *
                                map->n_max_cores_per_socket + core_id) *
                               map->n_max_ht_per_core + ht_id;

                if (((ht_id < map->n_ht_per_core) &&
                     (map->map[pos] == -1)) ||
                    ((ht_id >= map->n_ht_per_core) &&
                     (map->map[pos] != -1)))
                    return -1;
            }

        for ( ; core_id < map->n_max_cores_per_socket; core_id++)
            for (ht_id = 0;
                 ht_id < map->n_max_ht_per_core;
                 ht_id++) {
                uint32_t pos = cpu_core_map_pos(map,
                                                socket_id,
                                                core_id,
                                                ht_id);

                if (map->map[pos] != -1)
                    return -1;
            }
    }

    return 0;
}

#define FILE_LINUX_CPU_N_LCORES \
    "/sys/devices/system/cpu/present"

static int
cpu_core_map_get_n_lcores_linux(void)
{
    char buffer[64], *string;
    FILE *fd;

    fd = fopen(FILE_LINUX_CPU_N_LCORES, "r");
    if (fd == NULL)
        return -1;

    if (fgets(buffer, sizeof(buffer), fd) == NULL) {
        fclose(fd);
        return -1;
    }

    fclose(fd);

    string = index(buffer, '-');
    if (string == NULL)
        return -1;

    return atoi(++string) + 1;
}

#define FILE_LINUX_CPU_CORE_ID \
    "/sys/devices/system/cpu/cpu%" PRIu32 "/topology/core_id"

static int
cpu_core_map_get_core_id_linux(int lcore_id)
{
    char buffer[64];
    FILE *fd;
    int core_id;

    snprintf(buffer, sizeof(buffer), FILE_LINUX_CPU_CORE_ID, lcore_id);
    fd = fopen(buffer, "r");
    if (fd == NULL)
        return -1;

    if (fgets(buffer, sizeof(buffer), fd) == NULL) {
        fclose(fd);
        return -1;
    }

    fclose(fd);

    core_id = atoi(buffer);
    return core_id;
}

#define FILE_LINUX_CPU_SOCKET_ID \
    "/sys/devices/system/cpu/cpu%" PRIu32 "/topology/physical_package_id"

static int
cpu_core_map_get_socket_id_linux(int lcore_id)
{
    char buffer[64];
    FILE *fd;
    int socket_id;

    snprintf(buffer, sizeof(buffer), FILE_LINUX_CPU_SOCKET_ID, lcore_id);
    fd = fopen(buffer, "r");
    if (fd == NULL)
        return -1;

    if (fgets(buffer, sizeof(buffer), fd) == NULL) {
        fclose(fd);
        return -1;
    }

    fclose(fd);

    socket_id = atoi(buffer);
    return socket_id;
}

int
cpu_core_map_compute_linux(struct cpu_core_map *map)
{
    uint32_t socket_id, core_id, ht_id;
    int n_lcores;

    n_lcores = cpu_core_map_get_n_lcores_linux();
    if (n_lcores <= 0)
        return -1;

    /* Compute map */
    for (socket_id = 0; socket_id < map->n_max_sockets; socket_id++) {
        uint32_t n_detected, core_id_contig;
        int lcore_id;

        n_detected = 0;
        for (lcore_id = 0; lcore_id < n_lcores; lcore_id++) {
            int lcore_socket_id =
                cpu_core_map_get_socket_id_linux(lcore_id);

#if !defined(RTE_ARCH_PPC_64)
            if (lcore_socket_id < 0)
                return -1;
#endif

            if (((uint32_t) lcore_socket_id) == socket_id)
                n_detected++;
        }

        core_id_contig = 0;

        for (core_id = 0; n_detected ; core_id++) {
            ht_id = 0;

            for (lcore_id = 0; lcore_id < n_lcores; lcore_id++) {
                int lcore_socket_id =
                    cpu_core_map_get_socket_id_linux(
                        lcore_id);

#if !defined(RTE_ARCH_PPC_64)
                if (lcore_socket_id < 0)
                    return -1;

                int lcore_core_id =
                    cpu_core_map_get_core_id_linux(
                        lcore_id);

                if (lcore_core_id < 0)
                    return -1;
#endif

#if !defined(RTE_ARCH_PPC_64)
                if (((uint32_t) lcore_socket_id == socket_id) &&
                    ((uint32_t) lcore_core_id == core_id)) {
#else
                if (((uint32_t) lcore_socket_id == socket_id)) {
#endif
                    uint32_t pos = cpu_core_map_pos(map,
                                                    socket_id,
                                                    core_id_contig,
                                                    ht_id);

                    map->map[pos] = lcore_id;
                    ht_id++;
                    n_detected--;
                }
            }

            if (ht_id) {
                core_id_contig++;
                if (core_id_contig ==
                    map->n_max_cores_per_socket)
                    return -1;
            }
        }
    }

    return 0;
}

void
cpu_core_map_print(struct cpu_core_map *map)
{
    uint32_t socket_id, core_id, ht_id;

    if (map == NULL)
        return;

    for (socket_id = 0; socket_id < map->n_sockets; socket_id++) {
        printf("Socket %" PRIu32 ":\n", socket_id);

        for (core_id = 0;
             core_id < map->n_cores_per_socket;
             core_id++) {
            printf("[%" PRIu32 "] = [", core_id);

            for (ht_id = 0; ht_id < map->n_ht_per_core; ht_id++) {
                int lcore_id = cpu_core_map_get_lcore_id(map,
                               socket_id,
                               core_id,
                               ht_id);

                uint32_t core_id_noncontig =
                    cpu_core_map_get_core_id_linux(
                        lcore_id);

                printf(" %" PRId32 " (%" PRIu32 ") ",
                       lcore_id,
                       core_id_noncontig);
            }

            printf("]\n");
        }
    }
}

uint32_t
cpu_core_map_get_n_sockets(struct cpu_core_map *map)
{
    if (map == NULL)
        return 0;

    return map->n_sockets;
}

uint32_t
cpu_core_map_get_n_cores_per_socket(struct cpu_core_map *map)
{
    if (map == NULL)
        return 0;

    return map->n_cores_per_socket;
}

uint32_t
cpu_core_map_get_n_ht_per_core(struct cpu_core_map *map)
{
    if (map == NULL)
        return 0;

    return map->n_ht_per_core;
}

int
cpu_core_map_get_lcore_id(struct cpu_core_map *map,
                          uint32_t socket_id,
                          uint32_t core_id,
                          uint32_t ht_id)
{
    uint32_t pos;

    if ((map == NULL) ||
        (socket_id >= map->n_sockets) ||
        (core_id >= map->n_cores_per_socket) ||
        (ht_id >= map->n_ht_per_core))
        return -1;

    pos = cpu_core_map_pos(map, socket_id, core_id, ht_id);

    return map->map[pos];
}

void
cpu_core_map_free(struct cpu_core_map *map)
{
    free(map);
}
